


Black & White Swan

by StarLightCrystal



Category: TOMORROW X TOGETHER | TXT (Korea Band)
Genre: Alternate Universe, Alternate Universe - Harry Potter Setting, Alternate Universe - Hogwarts, Alternate Universe - Soulmates, Fluff, M/M, Patronus Charm (Harry Potter), Soulmates, Whipped Choi Beomgyu, Whipped Kang Taehyun
Language: English
Status: In-Progress
Published: 2021-03-05
Updated: 2021-03-12
Packaged: 2021-03-18 20:00:28
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 3,677
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29863299
Author URL: https://archiveofourown.org/users/StarLightCrystal/pseuds/StarLightCrystal
Summary: Patronuses can do many things. It can show what type of person you are, it can fight off dementors, and it can also show your soulmate?Choi Beomgyu, our favorite Gryffindor, has been practicing the Patronus Charm the past few days. Kang Taehyun, our favorite Ravenclaw has already mastered his Patronus, but its changed...?
Relationships: Choi Beomgyu/Kang Taehyun, Choi Soobin/Choi Yeonjun
Comments: 2
Kudos: 42





	1. Chapter 1

**Author's Note:**

> Not beta read, enjoy!

“You’re still in here?” A voice said behind Beomgyu. He turned around and met face to face with the Slytherin prefect.

“I- How did you find me?” 

Yeonjun chuckled and walked closer to the Gryffindor, “How would I not know where my best friend is?” He patted Beomgyu on the back, “Still trying to make that patronus?”

Beomgyu sighed, “I’ve been trying for the past few days and it just isn’t working!” He lets out a defeated groan before laying on the floor.

“Beom you know it takes time,” Yeonjun sat down on the floor next to Beomgyu, “Are you sure you’re thinking of your happiest memory?”

“What other memory would I be thinking of besides my happiest? And how did you get in here?”

“Didn’t we clear this already? I’m your best friend, of course I know where you are!”

“But I’m in the Room of Requirement! How could you find me?” An incredulous look crossed the boy’s face. He had specifically wanted a room suited for late night practices; where people wouldn’t be able to barge in and catch him.

Yeonjun chuckled, “I walked by thinking _I need to go in the room Beom uses for late night practices without getting caught._ Maybe you should request a room with more security measures.” 

The boy sat up and weaved his hand through his hair, “I guess you finding me doesn’t count as getting caught.”

“Guess not,” the Slytherin waved his hand around, “It's nearly 2 in the morning, you should really go back to your dorm.”

The latter sighed, “I’ll so get caught at this time.”

“Lucky for you, the Room of Requirement is on the same floor as the Gryffindor Tower. And tonight it’s the Hufflepuff Soobin and I who are on duty. You know Soobin wouldn’t have the heart to write you down."

“Surely a teacher could pop up out of nowhere. Even if Soobin is too nice to turn me in, I’m certain any teacher who found me would give me detention.” 

Yeonjun smirked, “But...you’re also in the Room of Requirement. I think you could just ask for a secret passage to your dormitory.”

“You can do that?”

The latter shrugged, “I mean I haven’t tried it, but it wouldn’t be impossible.” 

Grinning, Beomgyu jumped to his feet and started wishing for a secret passage to his dorm. He paced around, crossing his fingers in hope that the Room of Requirement would hear his pleads. 

“Beom, turn around!” The Slytherin said excitedly.

Opening his eyes, Beomgyu turned around and a huge smile crossed his face. The huge fireplace that once stood, was now replaced with a wooden door. He pulled the latch and peered inside, noticing the dark tunnel. Squinting, he made out the figure of his dorm at the very end. “It worked! Does this mean I can come here from my room whenever I want?"

Yeonjun shrugged and peered inside, “Looks dark in there...are you sure this is gonna work?”

“If you don’t see me at breakfast tomorrow, you’ll know where to find me.” Beomgyu winked before heading into the tunnel. He gave a quick wave to the elder and closed the door. “ _Lumos,_ ” he chanted and watched as his wand lit up. It wasn’t often for students to know about the Room of Requirement. He had only discovered it through his parents- who used it for who knows what back when they were at Hogwarts. The boy had sent countless letters back home wanting to find a place to be able to practice late a night and from the stories his father had told, he knew his father would be able to find him one. 

“ _Nox._ ” He whispered as soon as he approached the dorm, the light vanishing from his wand. When he fully stepped into the room, the existing tunnel behind disappeared. Beomgyu made his way over to his bed, careful to not wake his roommates. Once he settled down, he looked up at the ceiling. Charms was one of Beomgyu’s best subjects. Out his whole entire year, he was probably the best at it- yet after trying for days he still couldn’t summon The Patronus Charm. It being annoying was an understatement, it was incredibly frustrating. The only other time he had this much trouble with casting a charm was when he wanted to learn nonverbal spells. Those gave him a headache, but he doesn’t regret learning them at all.

***

The next morning, Beomgyu finds himself skipping breakfast and approaching the Room of Requirement. It’s not that he didn’t want to eat, it’s just after thinking about The Patronus Charm last night, he felt like he would be able to do it. Closing the door behind him, he reached in his pocket and drew out his wand. Standing in place, he allowed his eyes to close and thought of his happiest memories. 

“ _Expecto Patronum!”_ he shouts while waving his wand in small circles. A rush of magic runs through him. Snapping his eyes open, he beams at the silver light coming from the tip of his wand. 

“God dammit! Beomgyu are you in here?” 

Jumping, the Gryffindor turns around to face 4 boys. His concentration breaks and the light disappears. “Yeonjun-hyung,” He says, rubbing the tip of his wand, “What are you doing here?”

“Oh my god, Beom you’re okay!” The Slytherin Prefect ran over to the younger boy and squeezed him in a hug, “You weren’t here at breakfast this morning I was so worried you got stuck in the tunnel!”

Beomgyu rolled his eyes and pushed the boy off of him, “First of all, I’m fine. Second of all, I almost performed the Patronus but you interrupted me and third? Why are you bringing other people here!”

“First of all, I was worried. Second of all, you can conjure it another time. And third, these aren’t ‘other people’, it’s Soobin, Kai, and Taehyun- you know them!.” Yeonjun sassed back, hands on his hips.

The 3 said boys stood there as the Gryffindor and Slytherin fought. Anyone who watched this fight would know it was light hearted. The two had been friends ever since Beomgyu arrived at the school in his first year. People often thought it was strange that a Gryffindor and Slytherin could get along so well. 

After a while, a dolphin scream erupted out of the trio. The two boys fighting, glared at the three before strutting over.

“Kai, that was unnecessary.” Yeonjun huffed and poked the younger boy in the stomach. 

The boy let out another unnecessary scream before laughing. “Not like you two would stop fighting if I didn’t scream.”

“Introduce me to them?” Beomgyu asked, eyeing the trio. Certainly he knew who they were, but he didn’t know them. 

Yeonjun rolled his eyes and pointed at the boys, “The one who let out the ungodly scream is Kai. You know who Soobin is, the Hufflepuff Prefect that’s too nice to turn anyone in,” a _hey_ was heard, “And that’s Taehyun.” 

“Just Taehyun…?”

“Taehyun who’s good at literally anything. I brought them here today to help me find you, but you’re right here. I’m sure Taehyun could help you with summoning the Patronus though.”

“He can?”

“Um I guess I could,” The Ravenclaw spoke out, weaving his fingers through his blonde hair, a hint of red painted on his cheeks, “I conjured it a few weeks ago.”

The Gryffindor grinned, “I guess a little help won’t be rejected...but I’m telling you! I almost conjured it before you all barged into here!” 

“Your fault,” Yeonjun hissed out, “You told me to come find you if you didn’t so up to breakfast the next morning and you didn’t.”

“Well, today is Saturday so we can just chill here,” Soobin said, plopping down on a nearby beanbag. Beomgyu looked around and noticed the Room of Requirement had changed a little. Before, it was nothing but an empty room- perfect for practicing. Now, 5 bean bags were spread out on the floor and shelves full of games occupied the corner. He wondered how the room transformed so quickly without the boy noticing. 

“Soobinnie-hyung! Let’s play Wizarding Chess!” The younger Hufflepuff said, pulling out the set of Wizard’s Chess from the shelf. A table appeared as the boy plopped down in his own bean bag next to the older Hufflepuff. Soobin shrugged. Sitting up straighter, he helped the younger set up. 

“YJ you wanna learn the Patronus too?” Beomgyu asked, drawing his wand out once more. The elder waved his wand around and shrugged. Beomgyu took that as a _yes_ before turning around to Taehyun, “Mr. Kang please do us the pleasure of assisting us,” a twinkle present in his eyes.

Taehyun chuckled before lifting his own wand, “Let’s see if I can actually do it? _Expecto Patronum!”_ A silverish light flowed out from the tip of the Ravenclaw’s wand. Slowly, the light turned into a white mare. The 5 boys gasped as the horse pranced around them, it wasn’t everyday you see a Patronus conjured. For Beomgyu, it was his first- and it was absolutely stunning. Standing up straighter, Taehyu put his wand down and watched as the mare disappeared. 

“Taehyunnie you’re so cool! No wonder you’re my best friend!” Kai cheered from the floor giving a thumbs up. The Ravenclaw grinned and returned the gesture. Feeling the gaze of the Gryffindor and Slytherin, Taehyun felt his cheeks warm up. 

“Y-you did that so easily!” Beomgyu gaped, “I’ve been working on it for 3 days and the closest I’ve gotten to it was today!” 

Taehyun rubbed his neck and looked down at the floor, “I practiced for about a week before being able to conjure one.”

“So it should take me...3 more days and I should be able to do it?” The Gryffindor wonders out loud, counting on his fingers the days he’s already practiced. For the past 4 days, he has been staying in this room till late night. It was a surprise that the boy didn’t look like a wreck with the lack of sleep and food he has been getting. 

“Maybe you’ll be able to get it even quicker, since you said you almost got it before Yeonjun-hyung burst in.”

“GAHHHHH!”

“Shut up Kai!” The 3 standing boys yelled back, turning to the 2 playing Wizarding Chess. A proud smile danced on the older Hufflepuff’s face as the younger sported a frown. 

Soobin moved his piece and the younger glared, “Checkmate Huening, you had no chance of beating me.”

“Soobin-hyung, we haven’t even been playing for like 10 minutes!”

“Kai you just suck.” Yeonjun teased, sticking out his tongue. 

“I do not!” Kai replied, mimicking the older actions. They glared at each other before breaking into giggles. “Well since _Soobin-hyung_ cheated and beat me, the two of us can practice the Patronus too.” 

“You can say whatever you want Huening, but Yeonjun-hyung is right- you’re just bad.” The Hufflepuff grinned and stood up, stretching his arms, “Now Taehyun how do I do this?” 

Taehyun grinned and raised his wand, “As you all know, the Patronus incantation is _Expecto Patronum._ While doing this spell you must think of your happiest memory, or else it won’t work. You want to move your wand in a small circling motion.” The four boys mimicked the Ravenclaw’s wand motion and started chanting. Nothing much happened in the room- as the Patronus was a hard charm to manage. Taehyun weaved between the four, giving the necessary advice to each person. 

Reaching Beomgyu, he stood behind and watched the boy. “Beomgyu-hyung, maybe try moving your wand like this.” He clasps his hand over the elder’s hand gently and moves them in circular motion. 

Pink dusted on both of their cheeks, before Taehyun let go and watched the Gryffindor continue. A surge of happiness filled him up as a silverish light started coming out from Beomgyu’s wand. He directed it towards the shelves and a white swan appeared, flying around. “Look, look, look!” He cheered and the three paused their practice and faced the Gryffindor. Excitement, joy, and a hint of jealousy passed through their faces, but nevertheless cheers filled the room. 

Beomgyu watched as his Patronus gracefully fluttered across the room. White particles raining down on the group. He glowed with joy as the swan settled down on a small patch of water just appearing in the corner of the room. There, it floated elegantly and Beomgyu let out a sigh of content, “It’s...beautiful.” 

Yeonjun grinned and crushed him in a hug, “You did it Beom!” 

He laughed and returned the gesture, “It’s all thanks to Taehyun,” he turned to the said boy and gave a wink. Taehyun felt his face flush, replying with a _I didn’t do too much._ He fidgeted with his hands, nervously, until a stare burned into his back and he turned around.

 _Whipped,_ Huening mouthed with the playful smile of his and a hint of mischievous flashing through his eyes. Glaring, Taehyun plopped down in a beanbag before sitting back up abruptly. “Shit,” he swore out loud and stood up. Patting down his robes he stumbled towards the door.

“Taehyun-ah, where are you going?” Soobin said, striding towards the younger, a look of worry plastered across his face.

“Qudditch practice. Totally forgot. I’ll meet you guys at dinner.” Taehyun replied before rushing out the door. The four boys stood there and stared at each other in confusion. 

“Um...shall we continue practicing?” 


	2. Chapter 2

**Notes for the Chapter:**

> Not beta read

The following days, Taehyun finds himself spending more and more time in the Room of Requirement. Not only after school, but also late at nights. His sleep suffered greatly, but he just couldn’t resist the four boys' charms- not that he would ever admit it outloud. Ever since Beomgyu was able to conjure the Patronus, Yeonjun had followed along rather quickly. Producing a vicious wolf that had raced around the room as soon as it was conjured. Soobin and Huening weren’t far behind. Silver sparkles sparked from their wands everytime they chanted the incantation, it won’t be long until they’ve produced their own patronus. 

“Taehyunnie~!” A voice called from behind, the owner giggled before jumping on Taehyun from behind. “Going to the room again?”

Taehyun groaned from the weight and nodded, “The library is full and the common room is too. I wanted to study in peace.” He pushed the boy off and continued his walk, ignoring the whines coming from Hueningkai.

“You sure you only want to study?” The Hufflepuff asked, catching up to the Ravenclaw’s pace. “Maybe...there’s a certain someone you wanted to see…?” He wiggled his eyebrows and painted on a goofy smile. 

The Ravenclaw felt a blush crawl on his face and elbowed the boy in response. It wasn’t a lie that both the library and common room was filled, but Taehyun could study any day amidst the chaos. As long as he had his materials in front of him, he could zone out all the noise around him. So why go to the Room of Requirement when he could stay in the Ravenclaw’s comfy common room? Maybe it really was because of a certain someone.

Taehyun approaches the door to the Room of Requirement. It seems to just appear without much thought these days. When Yeonjun first brought him, Soobin, and Kai here, it was merely a wall. Taehyun couldn’t believe his eyes when the wall slowly transformed into a door. It has always been a rumor there was a special room on the 7th floor of Hogwarts, but Taehyun never believed in rumors. 

Pushing the door open, he notices the room’s slightly different appearance. Instead of the usual beanbags and shelves of games, the room was now filled with multiple tables and chairs, games replaced with books. A glamorous chandelier hung above them as he sat down at the nearest table. It seemed that as a different person went into the room today, the design was different too. 

“Looks like the library in here doesn’t it?” Kai motioned at the shelves and took out a few pieces of parchment. “I’ve got potions homework...please help!” 

Taehyun peered at the parchment and frowned. It seems Kai had already started some of it, but hadn’t continued; the topic seemed to be from last week. “And this is about antidotes for common poisons?”

The Hufflepuff nodded quickly.

“Wasn’t this due last week?”

Huening’s eyes widened and a sheepish smile formed on his lips, “I might’ve forgotten...but being one of the professor's favorite students, he’s given me an extension!”

Taehyun shook his head in disapproval and put down the parchment, “it still puzzles me how you can be so close with a Slytherin teacher.” Waving his wand, abook floats out from a shelf and lands in front of Kai with a  _ thump.  _ “Use this book, you’ll find everything you need in chapters 5 to 7.”

“The whole point of asking you was so that I didn’t need to look through books!” The boy whined, but listened and opened the book to the said chapters. His eyes brightened as he flipped through the pages, “Your right, everything I need is here! How did you know it would be in here?”

The Ravenclaw shrugged and looked back at his own parchment, “Maybe because I actually do my work. We’ve got the OWLs this year, we can’t afford to fall behind.”

The boy hummed in response and continued his work. Time flies by with just the two of them inside the room. Every few moments, Taehyun would seek a glance at the door, hoping a certain brown haired boy would walk through. No such luck. The large grandfather clock struck a behind the duo, a signal that they’ve been inside for too long. The Ravenclaw puts down his books and stretches, leaning his back against the chair. “You finished with that essay?” 

Kai nodded, “Check it for me please?” He pushed the parchment forward. 

Taehyun tooked the parchment and looked over it, “Did you seriously spell  _ venom  _ with an  _ a?  _ It’s literally spelled in the book!”

Kai snatched the parchment back and made a few markings, “It’s not my fault that the book wasn’t clear enough.” He tucks the parchment away and stands up. Letting out a sigh as he stretches his arms. “Taehyunnie I’m starving, let’s get lunch.”

“Fine by me. Let’s eat outside though, I’m tired of being cooped up inside.” They headed towards the door and opened it, noticing the lack of students in the hallways. “Seems like everyone is outside anyways.” They nodded and made a quick trip to the Great Hall. 

“So...Beomgyu-hyung didn’t show up today,” Kai slyly remarked, taking a big bite out of the sandwich they just took from the lunch trolley. 

Taehyun shrugged, “I wasn’t waiting for him.” He ignored the eyebrow Kai raised. “It’s not like I always want to be around him. Just because I’m more present in the  _ room  _ these days, isn’t because of him.” 

“Whatever you say.”

Taehyun rolled his eyes at the response, but his face felt warm. They started making small talk as they approached the school’s courtyard. Although this morning the library and common room were filled, it had seemed every student was outside chilling. 

“Taehyun-ah! Huening!” A voice shouted. The duo turned towards the voice and noticed a familiar blur-haired Hufflepuff flailing his arms around, trying to get their attention. He was sitting on a blanket with two other familiar students. “Come join us!” 

Kai grinned and ran over to the trio. He immediately plopped in between the Hufflepuff and Slytherin, giggling when he almost knocked over Yeonjun. Taehyun gave a small smile and sat down next to the Gryffindor.

Beomgyu grinned, “Where were you guys?” 

“Just studying in the  _ room,”  _ Kai replied and pointed at the Ravenclaw. “Taehyunnie said he needed some peace and quiet.” 

“Oh that’s where you were,” Soobin chimed in. “I’ve been looking for you guys all morning.” 

Taehyun continued eating from his sandwich and listened to the conversation. It seemed that Yeonjun and Beomgyu just came back from Quidditch practice- not with their teams. It was common knowledge that Gryffindor and Slytherin rivalry was not to be messed with.

The five spent their afternoon just chilling and talking. Occasionally, Taehyun noticed how Beomgyu would shift his position so they sat closer to each other or so that their shoulders would touch. It seemed Kai sensed every move, as he flashed that annoying smile every single time. Taehyun didn’t bother mentioning it though, he didn’t want Beomgyu to think he didn’t like these  _ advances  _ (was that even the right word to call it?) because he didn’t mind it. Ever since Yeonjun dragged Soobin, Kai and and him to the Room of Requirement, he was able to get closer to the Gryffindor. Not only were they now in the same friend circle, they were also friends. 

Friends.

_ Friends.  _

The word felt bitter to Taehyun. Every time Beomgyu smiles at him, links arms with him, compliments him, he feels the heat rush to his face and his heart beats like crazy. And no, Taehyun isn’t dumb, he knows what these  _ feelings  _ were. He didn’t want to be just  _ friends,  _ he wanted to be something a little more. And fuck Kai for knowing that. Fuck Kai for knowing Taehyun had the hots for the Gryffindor the first day he walked in the Great Hall. 

“You good there?” 

Taehyun blinked at the voice and faced Beomgyu, “Uh ya...just thinking about stuff.”

Beomgyu’s eyebrows wrinkled in worry, “Anything you can talk to me about?” He rested a hand on Taehyun’s shoulders, leaning in to study the Ravenclaw’s face.

Taehyun’s eyes widened, but his voice never wavered. “It’s nothing you have to worry about.”  _ Because it’s about me liking you,  _ he thought.

The boy leaned back, flashing a bright smile, “If you ever need to talk to me, know that I’ll always be there for you.” 

Taehyun hummed in response as Beomgyu laid on his back, humming out a soft tune. 

**Notes for the Chapter:**

> Not as much Taegyu as I wanted...but Tyunning is cute too >_<
> 
> And....HAPPY BEOMGYU DAY! Don't forget to stream Maze in the Mirror <3333
> 
> Thank you for reading~ Stay tuned for the next part!

**Author's Note:**

> I've always loved TXT and Hogwarts AUs! So I decided add my writing to the pile~


End file.
